Preshrunk yarn or fabric



Nov. 3, 1953 A. F. BURKARDT PRESHRUNK YARN OR FABRIC Filed Dec. 3, 1949 Cot/0n I34 Rayon I56 I f w m Anfan FBu'r/rard/ Ill/always 1 Patented Nov. 3, 1953 PRE SH RUNK YARN OR FABRIC Anton F.-Burkardt, New York, N.- Y., assignor to Sativa Corporation, a corporation of New Jersey This invention relates to a method of producing pre-shrunk yarns or fabrics and the pro-ducts produced thereby-and more particularly to such a method for producing pre-shrunk yarns or fabrics containing bast fibres. The term pre-shrun applied to yarns and fabrics in this specification and claim means a yarn or fabric which is shrunkenbefore fabrication to the extent herein described and which is therefore comparatively shrink-proof. i This process employs the use of pre-shrunk degummed bast fibres such, for example, as fiax or hemp, which may be degummed as described in the copending application, Serial No. 103,262, filed July 6, 1949, in which is taught the art of degumming raw fibres and shrinking the same. A preferred form of raw fibre for treatment by the method described in the aforesaid copending application is described in the copending application, Serial No. 87,594, filed April 15, 1949.

No method or process has heretofore been known that would sufiiciently degum and preshrink bast fibers to the extent necessary to produce the degummed and pre-shrunk fibrils dis closed herein in commercial quantity until the method of vdegumming and pre-shrinking dis- "closed in the co-pending application Serial No.

103,262 aforesaid was invented. This enabled flax and hemp to be dry-spun on ordinary cotton spinning machinery and eliminated wet spinning heretofore necessary.

As no "sufliciently degummed and pre-shrunk bast fibrils were available, no pre-shrunk yarns "or fabrics could be made, either solely of degummed and pre-shrunk fibrils or such fibrils blended with other shrinkable fibers, such as cotton or rayon. It is for this reason that no degummed pre-shrunk staples for dry spinning, such for example as linen, have ever been avail- .able to the textile trade. In this connection, it

will be noted that degummed, pre-shrunk bast fibrils such as linen, for example, will not shrink more than 2%, and usually much less, when made into yarn and the yarn into fabric, while ordinary non-degummed hemp and flax (linen) as ard cotton or woolen machinery or for dry spinping. The yarns produced by retted linen fibre Application. December 3, 1949, Serial No. 130,933 1 Claim. (01. 139-426) are spun over special linen machinery by a wet spinning process to make the fibres soft and pliable, and the yarns or fabrics are later processed and degummed in yarn or fabric form. The resultant material however, is not shrink-proof.

The new method disclosed in the copending application, Serial No. 03,262 produces shrunk linen staples similar in staple length or fineness to cotton, which can be spun over standard cotton or woolen machinery. These fibre staples are as fine as 1 denier, so that they can be blended with synthetic fibres or rayon or others, or with fine wool or natural fibres, by dry spinning over any conventional textile machinery, which has never been possible before or practiced in the textile industry.

Linen staples produced by known methods of retting and processing cannot be spun or blended with fine'synthetics or natural fibres over standard textile machinery, nor will they reduce or eliminate the shrinkage of resulting yarns or fabrics, as is the case with shrunk linen produced under the process described in the aforesaid application, Ser. No. 103,262.

The instant invention is therefore directed to the use of fibrils of bast stalks that are degummed and pre-shrunk as taught in said application,

and fabrics produced thereby. It will be understood, however, that what is herein disclosed is merely illustrative and not limitative, and that various modifications can be made, the inven- 7 tion being defined by the appended claim.

In the accompanying drawings: Figure 1 illustrates a sliver or roving composed wholly of bast fibres to produce the pre-shrunk roving as defined under object (A) hereof I, Figure 2 illustrates a composite sliver or roving composed in part of pre-shrunk bast fibres and in part of other fibres to produce the roving as defined under object (B) hereof;

Figure 3 illustrates a composite yarn;

Figure 4 illustrates another composite yarn;

Figures 5 and 6 illustrate yarns as referred to under object (C) hereof; and

Figures '7 and 8 illustrate fabrics as referred to underobject (1D) hereof.

Referring to Fig. 1, if bast fibres are degummed to produce fibres of desired staple length and denier in a suitable degumming apparatus such as that for example described in the co-pending. application, Serial No. 103,262 aforesaid, or in any other suitable manner, where natural fibres are degummed, boiled off. and subiected to a rinse, the degummed washed fibre is pre-shrunk.

Under such treatment a web of natural fibre will shrink from a total length of 50 feet to 42 feet, and each fibril l thereof of course shrinks in proportion,

The o -shrunk web may now e pened up and arena-r d fo spinn n This pro u e dividual fibrils 10 of preeshrunk fibre and these may be from 1% to 2 /2 inches long and may average i /z denier. It will be observed that these fibres are obtained without cutting into predet mined l n t s, d t at the pe n up process results in the production of fibrils a herein referred stated in the aforesaid application, Serial No. 103,262, the length of the fibrils can be predetermined by controllin the treatment of the raw fibre and, depending upon said treatment, may "be made more or less receptive to standard dyes such as used for cotton, wool or synthetic fibres.

The fibrils In may now be formed into a sliver or roving H to be spun on standard existing textile machinery, and the resultant product will com-prise a pre-shrunk roving composed wholly of .bast fibres, which attains object (A) hereof and which may be used as hereinafter descr bed- Referring to Figure 2, the fibrils 10, instead of being made into a roving ll composed wholly of' them, are admixed with other fibres in any desired proportion to form a roving l2. This may be blended in any manner and may coinprise:

1. A mixture of 50% by weight of bast fibres I0 and 50% cotton l3, or wool M, or synthetic fibre I 5,'such as rayon.

2. Equal parts by weight of bast l0, wool l4, cotton 1:3 and rayon l5,v

In all cases the fibrilla readily mix and form a composite roving which may be produced on standard existing textile machinery and which, by reason of the presence of the pre-shrunk bast fibrils 1B is substantially shrinkeproof, the exact amount of shrinkage bein determined by the admixture .and the characteristics of the fibres 13, I4, l other than the pre-shrunk hast fibe n whi p events t e yarns ma e from such roving from shrinking. This occurs because the degummed pro-shrunk fibers prevent the other shrinkable fibers from shrinking when h er n t e it holdin sa d shrinkable fibers against longitudinal shrinking.

Thus is produced a composite roving containing pre-shrunk bast fibers which attains object (B) hereof and which may be used as heIBinafter described.

Referring to Figure 3, a composite yarn is shown at l2a made of wool, pre-shrunk linen (bast staples), rayon and cotton blended or mixed in any manner and proportions.

Referring to Figure 4, a composite yarn I6 is shown consisting of the pre-shrunk linen roving H (or the composite roving l2) and rovings of cotton l3a, wool [4a and rayon l5a.

Referring to Figure 5, a 2-ply yarn is shown consisting of a rayon roving 1.50. and the roving H .(or 12)..

Figure 6 shows a 2-ply yarn consisting of a wool roving Ma. and the roving H (or l2).

Obviously the composition of the yarns, Figs. 5 and 6 can be varied within wide limits, but in all cases the presence of the pre-shrunk fibrils ll) the yarn results in a pre-shrunk yarn which attains object ((3) hereof.

A 4/1 yarn made as described herein and composed of rovings H has the following characteristics;

Comparative breaking strength Dry Wet Hot Wet 5 316 lbs. 726 lbs.

510 lbs.

% increase normal ,to hot Referring to Figure '7, the numeral 1 1 generally denotes a fabric including pre-shrunk yarn as previously described.

Now the extent of the use of such pre-shrunk yarn in the fabric may be varied within wide limits, and the pre-sh-runk quality of the fabric may be varied accordingly.

Assuming for the sake of illustration that preshrunk yarn is used in the fabric, it may constitute all the warp yarns IB and be as described in connection with the preceding figures or constitute all the filler threads l9 and be as described in connection with Fig. 4, or constitute a part of the warp or a part of the filler, or part of 'both.

In Fig. 8 a construction is shown where a yarn l2a, Fig. 3 may be used.

A fabric made entirely from preeshrunk bast yarn is substantially shrink-proof, is stronger wet than dry, and withstands repeated washing and ironing with less wear and tear than known fabrics having the same denierv and weightzcharacteristics.

Fabrics made from any of the yarns herein described will have all orsome portion of their surface composed of the fibrils 10 of the preshrunk fibre. The extent of said surface will depend upon the construction of the yarn which obviously depends upon. the use of. the fabric in which it is used, and the amount of it used-in the fabric,

'It' would :be difficult indeed to recite even a few .of the combinationspossible and it is not deemed necessary to do so in view of the fact-that once the inventive concept herein disclosed is understood, it is merely a matter of selecting the amount of preeshr-unk fibrils .to be usedin the staple or roving to make :the yarns and the construction of the fabric usingthe selected yarn.

This specification employs the terms fshrinkproof," comparatively shrink-proof andfsubstantia'l'ly shrink=pro=ofto describe that quality which is commonly termed shrinkeproof'found in 'rovings; yarns and fabrics that will shrink less than 2%. No fiber made today is absolutely shrink-proof." However, American Standards Association System has defined shrink-proof and substantially shrink-proof fabrics to mean that the shrinkage of such rovings, yarns or fabrics will be not more than 2%. This specification therefore employs these terms as they are commonly understood in this art.

As previously stated herein, the composition of the yarns (Figures 5 and 6) may be varied within wide limits, and by way of illustration, a cloth made of 30% of yarn (Figure 1 and Figure 5) of degummed and pre-shrunk linen fibers, and 70% viscose rayon (Figure 5) will not shrink or elongate more than .0136%, which is less than the 2% specified in the American Standards Association System referred to above. The same shrink-proof qualities apply to a mixture of yarn (Figure 1) with 75% viscose rayon. As heretofore pointed out, the extent of this use of such pre-shrunk yarn (Figure 1) with other yarns can be varied within wide limits, and the shrink-proof quality of fabrics made therefrom may be varied accordingly.

Linen produced by the above described method has superior ironability, a term used in the trade to denote that the goods will withstand high ironing temperatures, the pre-shrunk degummed fibers which are tubular and have cellular walls acting to insulate the other fibers interspun therewith and insulate them from heat. Cloth made from a mixture of degummed and pre-shrunk linen fibers and 70% viscose rayon will shrink less than 2% when washed repeatedly or even boiled, and will withstand ironing temperatures of 300 to 350 F. without becoming tackey and without the iron sticking to the goods and without damage.

A common test for ironability is to place a cigarette paper on the goods and an approximately 350 F. iron thereto. With ordinary goods not containing the degummed and pre-shrunk fibers disclosed herein the paper is browned; the iron sticks to the goods. When the above rayon degummed linen mixture is used, the paper will brown but the iron will not stick to the goods because of the insulating qualities of the degummed pre-shrunk fibers.

As previously stated herein, a suitable method of degumming and shrinking the bast fiber is referred to in the co-pending application Serial Number 103,262 which discloses a chemical degumming process, the bast fiber being immersed in a chemical bath until the desired amount of gum is extracted therefrom to permit the fibers to be dry-spun over standard cotton or woolen machinery as aforesaid. Obviously any method of degumming that will not remove the desired amount of gum to permit the fibers to be dryspun cannot be employed. As stated in said copending application Serial Number 103,262, the exact degumming fluid employed and the time the fiber is immersed therein depends upon the character of the fiber.

What is claimed is:

A fabric having substantially non-shrinkable qualities, said fabric being composed of dry-spun yarns, said yarns being blended in part of staples of degummed and substantially completely preshrunk flax or hemp fibrils, and in part of other shrinkable fibrils.

ANTON F. BURKARDT.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 8,134 Claussen June 3, 1851 9,650 Pownall Apr. 5, 1852 679,695 Ellis July 30, 1901 882,866 Butterworth Mar. 24, 1908 1,313,594 Hartshorne Aug. 19, 1919 1,607,220 Von Ehrenthal et a1. Nov. 16, 1926 1,986,970 Haughey Jan. 8, 1935 2,070,273 Haughey Feb. 9, 1937 2,122,175 Coulter June 28, 1938 2,128,929 Estes Sept. 6, 1938 2,230,269 Pierce Feb. 4, 1941 2,260,229 Nutter et a1 Oct. 21, 1941 2,371,573 Sabner Mar. 13, 1945 2,468,771 Montonna et al May 3, 1949 FOREIGN PATENTS Number Country Date 309,367 Great Britain Apr, 11, 1929 

